However, Russian Federal Security Service (FSB) chief Alexander Bortnikov said on Tuesday that a homemade explosive device was placed on the plane that caused it to explode and break mid-air while it was flying from the popular Sharm el-Sheikh resort on the Red Sea to St Petersburg.

He said that the bomb was equivalent of up to one kg of TNT, Russia's Tass news agency reported.

Russian President Vladimir Putin has vowed to 'find and punish' those behind the terror act, according to the news agency.

"The murder of our nationals in Sinai is among the bloodiest crimes as to the number of casualties. We will be searching them (terrorists) everywhere, no matter where they hide. We will find them in any point of the globe and they will be punished," Putin said.